That's generally true, but not in all cases.
Because I have Crohn's Disease, I've toyed with the idea of creating an app that would let a patient track their symptoms and diet, etc., to figure out what are the factors that cause a flare-up for them; and later upload the history to their doctor. But knowing (a) the regulations in the USA surrounding medical devices (does this count as one? who knows without a lawyer) and (b) the potential for liability for even the stupidest things, I've decided that the potential danger for me is nowhere near worth it.